This research is concerned with understanding the physiology of taste and cutaneous senses including the coding of the sensory information transmitted to the brain. One objective is to advance our understanding of the sense of taste in mammals, with particular reference to the hedonic properties of taste solutions. Why are some taste solutions preferred and others avoided? The problem will be approached using electrophysiological and behavioral techniques. A second objective is to elucidate the basic developmental interactions between taste nerve fibers and the epithelial cells which are precursors of the receptor cells. These processes include the differentiation and maintenance of the receptor cells (trophic dependency upon nerve supply) and the interactions leading to the formation of synaptic connections with the receptor cells. If the rules of connectivity in the taste sensory system can be outlined, then it will be appropriate to examine environmentally induced plasticity in neuronal connections. Anatomical, physiological, biochemical and behavioral techniques will be brought to bear upon these problems.